Diabetic macular edema constitutes the largest single cause of visual impairment in patients with diabetic retinopathy. A detailed study of the natural history of patients with diabetic macular edema will be conducted with special emphasis on the perifoveal capillary perfusion patterns as demonstrated by fluorescein angiography. Controlled studies on techniques of photocoagulation in the management of diabetic macular edema will be investigated. BIBLIOGRAPHIC REFERENCES: Patz, A., Fine, S.L., & Yassur, Y.: -Management of Diabetic Maculopathy. Chapter in Proceedings of International Photocoagulation Congress held October 1975, in press 1976, C.V. Mosby Co. Patz, A., Fine, S.L. & Finkelstein, D.: - Natural History and Photocoagulation Studies in Diabetic Macular Edema. Chapter in Principles of Photocoagulation, edited by H. Christian Zweng, in press, 1976, Little, Brown & Co., Boston.